>perl -le"system 'foo'; print $?==-1 ? qq{$!=\$!} : qq{\$?=$?}"
'foo' is not recognized as an internal or external command,
operable program or batch file.
$?=256

##</code><code>##

>perl -le"system({ 'foo' } 'foo'); print $?==-1 ? qq{$!=\$!} : qq{\$?=$?}"
$?=65280